Plate heat exchanger with improved connection strength of adjacent heat exchange plates

ABSTRACT

A plate heat exchanger includes a number of first heat exchange plates and a number of second heat exchange plates. The first heat exchange plate includes a first wave crest and a first wave trough. The second heat exchange plate includes a second wave crest and a second wave trough. Along a thickness direction, a maximum distance between the first wave crest and the first wave trough is h. In a direction of a shortest line connecting tops of adjacent first wave crests, a minimum connecting width of the first wave trough and the second wave crest is W1, and a minimum connecting width of the first wave crest and the second wave trough is W2. At least one of a ratio of W1/h and a ratio of W2/h is within a range of 0.25 to 2.5 to ensure the connection strength between adjacent heat exchange plates.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims priority of a Chinese Patent ApplicationNo. 202210456457.8, filed on Apr. 28, 2022 and titled “PLATE HEATEXCHANGER”, the entire content of which is incorporated herein byreference.

TECHNICAL FIELD

The present disclosure belongs to the field of heat exchangers, and inparticular, relates to a plate heat exchanger.

BACKGROUND

Stainless steel plate heat exchangers are widely used in refrigerationand heating systems as evaporators, condensers, economizers, etc., dueto their advantages of compact structure, high heat exchangecoefficient, high reliability, and less refrigerant charge etc. Theplate heat exchanger is composed of stacked plates with corrugations.After multi-layer plates are stacked, two fluid channels are formed, andheat exchange is performed through the corrugations of the plates.

The plate heat exchanger is welded after stacking heat exchange plates.Adjacent heat exchange plates form a network of multi contact points,and inter-plate channels are formed between adjacent heat exchangeplates for medium fluid to flow for heat exchange. The connectionstrength of the contact point directly affects the working stability andservice life of the plate heat exchanger. Therefore, it is necessary topropose a plate heat exchanger to ensure the connection strength ofadjacent heat exchange plates.

SUMMARY

An object of the present disclosure is to provide a plate heat exchangerto ensure connection strength.

The present disclosure provides a plate heat exchanger, including:

-   -   a plurality of first heat exchange plates, the first heat        exchange plate including a first corrugation, the first        corrugation including a first wave crest and a first wave        trough; and    -   a plurality of second heat exchange plates, the second heat        exchange plate including a second corrugation, the second        corrugation including a second wave crest and a second wave        trough;    -   wherein the first heat exchange plate and the second heat        exchange plate are stacked alternately along a stacking        direction which is the same as a thickness direction of the        plate heat exchanger;    -   at least part of the second wave crest of the second heat        exchange plate is in contact with a corresponding first wave        trough of an adjacent first heat exchange plate which is located        adjacent to the second heat exchange plate; at least part of the        second wave trough of the second heat exchange plate is in        contact with a corresponding first wave crest of another        adjacent first heat exchange plate which is located adjacent to        the second heat exchange plate;    -   along the thickness direction of the plate heat exchanger, a        maximum distance between the first wave crest of the first heat        exchange plate and the first wave trough of the first heat        exchange plate is h; and    -   in a direction of a shortest line connecting tops of adjacent        first wave crests, in adjacent first heat exchange plate and        second heat exchange plate, a minimum connecting width of the        first wave trough and the second wave crest is W₁, and a minimum        connecting width of the first wave crest and the second wave        trough is W₂; wherein at least one of a ratio of W₁/h and a        ratio of W₂/h is within a range of 0.25 to 2.5.

For the plate heat exchanger provided in the present disclosure, theratio of the minimum connecting width between the wave crest and thewave trough of the heat exchange plate to the height of the corrugationis designed to be within the range of 0.25 to 2.5, which ensures theconnection strength between adjacent heat exchange plates of the plateheat exchanger.

BRIEF DESCRIPTION OF DRAWINGS

In order to more clearly illustrate the technical solutions in theembodiments of the present disclosure, the following will brieflyintroduce the drawings that need to be used in the description of theembodiments. Apparently, the drawings in the following description areonly some embodiments of the present disclosure. For those skilled inthe art, other drawings can also be obtained based on these drawingswithout any creative effort.

FIG. 1 is a structural view of a plate heat exchanger in accordance witha first embodiment of the present disclosure;

FIG. 2 is an exploded view of the plate heat exchanger in accordancewith the first embodiment of the present disclosure;

FIG. 3 a is a partial cross-sectional view of adjacent first heatexchange plate and second heat exchange plate in accordance with thefirst embodiment of the present disclosure;

FIG. 3 b is another partial cross-sectional view of the adjacent firstheat exchange plate and second heat exchange plate in accordance withthe first embodiment of the present disclosure;

FIG. 3 c is a partially exploded view of the adjacent first heatexchange plate and second heat exchange plate in accordance with thefirst embodiment of the present disclosure;

FIG. 3 d is a partial view of a front view of the plate heat exchangerin accordance with the first embodiment of the present disclosure;

FIG. 4 a is an enlarged view of circle A in FIG. 2 ;

FIG. 4 b is an enlarged view of circle B in FIG. 2 ;

FIG. 5 is a cross-sectional view of the plate heat exchanger inaccordance with a second embodiment of the present disclosure;

FIG. 6 is a partial cross-sectional view of adjacent first heat exchangeplate and second heat exchange plate in accordance with the secondembodiment of the present disclosure;

FIG. 7 is an enlarged view of circle C in FIG. 5 ;

FIG. 8 is a view of an arrangement of second wave crests and convexridges in a first implementation manner in accordance with the secondembodiment of the present disclosure;

FIG. 9 is a view of the arrangement of the second wave crests and theconvex ridges in a second implementation manner in accordance with thesecond embodiment of the present disclosure;

FIG. 10 is a view of the arrangement of the second wave crests and theconvex ridges in a third implementation manner in accordance with thesecond embodiment of the present disclosure;

FIG. 11 is a partially exploded view of adjacent first heat exchangeplate and second heat exchange plate in accordance with the secondembodiment of the present disclosure;

FIG. 12 is a front view of the first heat exchange plate in accordancewith a third embodiment of the present disclosure;

FIG. 13 is a front view of the second heat exchange plate in accordancewith the third embodiment of the present disclosure;

FIG. 14 is a partial view of a first corrugation and a secondcorrugation forming a network contact in accordance with the thirdembodiment of the present disclosure;

FIG. 15 is a partial view of a first flow guiding section in a secondimplementation manner in accordance with the third embodiment of thepresent disclosure;

FIG. 16 is a partial view of a second flow guiding section in a secondimplementation manner in accordance with the third embodiment of thepresent disclosure;

FIG. 17 is a partial view of the first flow guiding section in a thirdimplementation manner in accordance with the third embodiment of thepresent disclosure;

FIG. 18 is a partial view of the second flow guiding section in a thirdimplementation manner in accordance with the third embodiment of thepresent disclosure;

FIG. 19 is a structural view of stacked adjacent first heat exchangeplate and second heat exchange plate in accordance with an embodiment ofthe present disclosure;

FIG. 20 is a structural view of first ports and second ports with gapsin accordance with an embodiment of the present disclosure; and

FIG. 21 is an enlarged view of circle D in FIG. 5 .

DETAILED DESCRIPTION

Exemplary embodiments will be described in detail here, examples ofwhich are shown in drawings. When referring to the drawings below,unless otherwise indicated, same numerals in different drawingsrepresent the same or similar elements. The examples described in thefollowing exemplary embodiments do not represent all embodimentsconsistent with this application. Rather, they are merely examples ofdevices and methods consistent with some aspects of the application asdetailed in the appended claims.

The terminology used in this application is only for the purpose ofdescribing particular embodiments, and is not intended to limit thisapplication. The singular forms “a”, “said”, and “the” used in thisapplication and the appended claims are also intended to include pluralforms unless the context clearly indicates other meanings.

It should be understood that the terms “first”, “second” and similarwords used in the specification and claims of this application do notrepresent any order, quantity or importance, but are only used todistinguish different components. Similarly, “an” or “a” and othersimilar words do not mean a quantity limit, but mean that there is atleast one; “multiple” or “a plurality of” means two or more than two.Unless otherwise noted, “front”, “rear”, “lower” and/or “upper” andsimilar words are for ease of description only and are not limited toone location or one spatial orientation. Similar words such as “include”or “comprise” mean that elements or objects appear before “include” or“comprise” cover elements or objects listed after “include” or“comprise” and their equivalents, and do not exclude other elements orobjects. The term “a plurality of” mentioned in the present disclosureincludes two or more.

Hereinafter, some embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings. In thecase of no conflict, the following embodiments and features in theembodiments can be combined with each other.

First Embodiment

As shown in FIG. 1 , FIG. 2 , FIG. 3 a , FIG. 3 b and FIG. 7 , a plateheat exchanger provided in this embodiment includes a plurality of firstheat exchange plates 10 and a plurality of second heat exchange plates20. The first heat exchange plate 10 and the second heat exchange plate20 are alternately stacked. A stacking direction of the first heatexchange plates 10 and the second heat exchange plates 20 is the same asa thickness direction of the plate heat exchanger. The stacked heatexchange plates are integrated by welding (such as brazing). The firstheat exchange plate 10 has first corrugations 1. The second heatexchange plate 20 has second corrugations 2. The first corrugation 1includes a first wave crest 1 r and a first wave trough 1 g. The secondcorrugation 2 includes a second wave crest 2 r and a second wave trough2 g. At least part of the second wave crest 2 r of the second heatexchange plate 20 is in contact with a corresponding first wave trough 1g of an adjacent first heat exchange plate 10. At least part of thesecond wave trough 2 g of the second heat exchange plate 20 is incontact with a corresponding first wave crest 1 r of another adjacentfirst heat exchange plate 10.

Along the thickness direction of the plate heat exchanger, a maximumdistance between the first wave crest 1 r and the first wave trough 1 gof the first heat exchange plate 10 is h.

Specifically, at least part of a top surface of the first wave crest 1 rof the first heat exchange plate 10 is located in a first plane P1. Atleast part of a bottom surface of the first wave trough 1 g is locatedin a second plane P2. The first plane P1 is parallel to the second planeP2. A distance (i.e., a vertical distance) from the first plane P1 tothe second plane P2 is the same as h. At least part of a top surface ofthe second wave crest 2 r of the second heat exchange plate 20 islocated in a third plane P3. At least part of a bottom surface of thesecond wave trough 2 g is located in a fourth plane P4. The third planeP3 is parallel to the fourth plane P4. A distance (i.e., a verticaldistance) from the third plane P3 to the fourth plane P4 is the same ash. The third plane P3 of the second heat exchange plate 20 coincideswith the second plane P2 of the adjacent first heat exchange plate 10.The fourth plane P4 of the second heat exchange plate 20 coincides withthe first plane P1 of the another adjacent first heat exchange plate 10.In this embodiment, optionally, the top surfaces of the first wavecrests 1 r of the first heat exchange plates 10 are all located in thefirst plane P1, the bottom surfaces of the first wave trough 1 g are alllocated in the second plane P2, the top surfaces of the second wavecrests 2 r of the second heat exchange plates are all located in thethird plane P3, and the bottom surfaces of the second wave troughs 2 gare all located in the fourth plane P4.

In this embodiment, the stacking direction (an X direction shown in FIG.1 ) of the first heat exchange plates 10 and the second heat exchangeplates 20 is perpendicular to the first plane P1, that is, the thicknessdirection of the plate heat exchanger is perpendicular to the firstplane P1. In this embodiment, the stacking order of the first heatexchange plates 10 and the second heat exchange plates 20 is notspecifically limited, it may be that the first heat exchange plate10-the second heat exchange plate 20-the first heat exchange plate 10are stacked in sequence, or it may be the second heat exchange plate20-the first heat exchange plate 10-the second heat exchange plate arestacked in sequence.

The plate heat exchanger is connected by corresponding wave crests andwave troughs, forming a network of multi-point contacts. During the heatexchange process of the plate heat exchanger, the medium flows back andforth between these contacts. Moreover, the corrugation of the plate canmake the medium form a turbulent flow at a lower Reynolds number toachieve better heat exchange performance. If the connection fastnessbetween adjacent heat exchange plates is low, there will be problems ofpoor working stability and even failure. In order to ensure theconnection strength between adjacent heat exchange plates and improvethe stability of the plate heat exchanger, the present embodimentperforms the following design on the connected wave crests and wavetroughs: referring to FIG. 3 a , FIG. 3 b again in conjunction with FIG.3 d , in a direction of a shortest line connecting the tops of theadjacent first wave crests 1 r (Y direction as shown in FIG. 3 d ), thatis, a direction of the line connecting the tops of the first wave crests1 r perpendicular to the first heat exchange plate 10, a minimum widthof the contact between the first wave trough 1 g and the second wavecrest 2 r is W₁, a minimum width of the contact between the first wavecrest 1 r and the second wave trough 2 g is W₂, wherein at least one ofa ratio of W₁/h and a ratio of W₂/h is with a range of 0.25 to 2.5. Bydesigning the ratio of W₁/h and/or W₂/h in the range of 0.25 to 2.5, theproblems of false welding and insufficient welding caused by too littlecontact between the tops of the wave crests and the bottoms of the wavetroughs are avoided. At the same time, the excessive contact between theheat exchange plates caused by solder to occupy too many inter-platechannels, thereby affecting the heat exchange performance of the heatexchanger is avoided.

In order to ensure the connection width, in the direction of theshortest line connecting the tops of the adjacent first wave crests 1 r,an outer width of the bottom of the first wave trough 1 g that isconnected to the second wave crest 2 r is greater than or equal to W₁,an outer width of the top of the second wave crest 2 r that is connectedto the first wave trough 1 g is greater than or equal to W₁, an outerwidth of the top of the first wave crest 1 r that is connected to thesecond wave trough 2 g is greater than or equal to W₂, and an outerwidth of the bottom of the second wave trough 2 g that is connected tothe first wave crest 1 r is greater than or equal to W₂. In thisembodiment, optionally, in the direction of the shortest line connectingthe tops of the adjacent first wave crests 1 r, the outer width of thebottom of the first wave trough 1 g that is connected to the second wavecrest 2 r is W₁, the outer width of the top of the second wave crest 2 rthat is connected to the first wave trough 1 g is W₁, the outer width ofthe top of the first wave crest 1 r that is connected to the second wavetrough 2 g is W₂, and the outer width of the bottom of the second wavetrough 2 g that is connected to the first wave crest 1 r is W₂.

In this embodiment, along the thickness direction of the plate heatexchanger, the maximum distance between the second wave crest 2 r andthe second wave trough 2 g of the second heat exchange plate 20 is alsoh. It should be understood that due to the influence of machiningaccuracy, assembly accuracy and measurement errors, the distance fromthe first plane P1 to the second plane P2 is not absolutely equal to h,and a certain error is acceptable, for example, an error range is ±0.1h. Similarly, an error range of ±0.1 his allowed for coincident planes.In this embodiment, W₁ is equal to W₂. W₁ and W₂ here are not absolutelyequal, and an error range of ±0.3 mm between the two is acceptable.Therefore, the ratio of W₁/h is approximately the same as that of W₂/h,and his with a range of 1 mm to 2 mm in this embodiment. Of course, theratios of W₁ and W₂ may also be different (not shown in the drawings),so the ratio of W₁/h is different from that of W₂/h. W₁ can be chosen tobe greater than W₂, or smaller than W₂, or the same as W₂, according toactual needs.

Specifically, referring to FIG. 3 a , FIG. 3 b again in conjunction withFIG. 5 , the inter-plate channels of the plate heat exchanger include atleast one first channel 6 and at least one second channel 7. The firstchannel 6 is located between the second heat exchange plate 20 and theadjacent first heat exchange plate 10. The second channel 7 is locatedbetween the second heat exchange plate 20 and the another adjacent firstheat exchange plate 10. The first channels 6 communicate with eachother. The second channels 7 communicate with each other. There is nocommunication between the first channels 6 and the second channels 7. Inthis embodiment, the corrugation of the first heat exchange plate 10 andthe corrugation of the second heat exchange plate 20 are distributedsymmetrically, so the volume of the first channel 6 and the volume ofthe second channel 7 are approximately the same (as shown in FIG. 3 a ),or the volume of the first channel 6 and the volume of the secondchannel 7 have a relative big difference (as shown in FIG. 3 b ).

In this embodiment, wavelengths λ of the first wave crest 1 r, the firstwave trough 1 g, the second wave crest 2 r, and the second wave trough 2g are substantially the same. That is, a distance between adjacent firstwave crests 1 r, a distance between adjacent first wave troughs 1 g, adistance between adjacent second wave crests 2 r, and a distance betweenadjacent second wave troughs 2 g are the same. Of course, thewavelengths λ of the first wave trough 1 g and the second wave crest 2r, and the wavelengths λ of the first wave crest 1 r and the second wavetrough 2 g may also be different.

In order to further improve the connection strength between adjacentheat exchange plates after welding, referring to FIG. 3 c , in thisembodiment, the top of the first wave crest 1 r, the top of the secondwave crest 2 r, the bottom of the first wave trough 1 g and the bottomof the second wave trough 2 g are all straight portions 3 a which areflat. A contact surface of the straight portion 3 a is perpendicular tothe stacking direction. In other words, the tops of the first wave crest1 r and the second wave crest 2 r are the straight portions 3 a, and thebottoms of the first wave trough 1 g and the second wave trough 2 g arethe straight portions 3 a. During the welding process, the solder canfully contact the surfaces of the tops of the wave crests and thebottoms of the wave troughs, and fill between the corresponding straightportions 3 a, thereby increasing the contact area, reducing the problemof false welding, and further improving the welding strength.

In addition, in this embodiment, the first wave crest 1 r, the secondwave crest 2 r, the first wave trough 1 g and the second wave trough 2 gfurther include a first side wall portion 3 b and a second side wallportion 3 c. In the direction of the shortest line connecting the topsof the adjacent first wave crests 1 r, one side of the straight portion3 a is connected to the first side wall portion 3 b, and the other sideis connected to the second side wall portion 3 c. An angle α is formedbetween the first side wall portion 3 b and the second side wall portion3 c, where 120°≤α≤135°. In this embodiment, the first side wall portion3 b and the second side wall portion 3 c are symmetrical with respect tothe straight portion 3 a.

Second Embodiment

In this embodiment, the parts that are the same as in the firstembodiment are given the same reference numerals, and the same textdescriptions are omitted.

Compared with the first embodiment, the plate heat exchanger provided inthis embodiment has the following different designs.

Referring to FIG. 4 a , FIG. 4 b , and FIG. 5 to FIG. 7 , in order toimprove the heat exchange effect of the plate heat exchanger and preventthe heat exchange performance from being reduced due to excessivepressure loss during the heat exchange process, in this embodiment, thedesign of the second corrugation 2 is improved, and the firstcorrugation 1 is the same as that of the first embodiment. Specifically,the second corrugation 2 also includes at least one convex ridge 2 a.The convex ridges 2 a are distributed along a direction of a shortestline connecting the tops of adjacent second wave crests 2 r of thesecond heat exchange plates 20. Along the stacking direction (i.e.,along the thickness direction of the plate heat exchanger), a top of theconvex ridge 2 a is located between the top of the second wave crest 2 rand the bottom of the second wave trough 2 g. Along the stackingdirection, the first channel 6 and the second channel 7 are provided ontwo sides of the same convex ridge 2 a. The volume of the first channel6 and the volume of the second channel 7 are different. In thisembodiment, the convex ridge 2 a are provided on the second heatexchange plate 20 so that the volumes of the inter-plate channels (alongthe stacking direction) on two sides of the convex ridge 2 a of theplate heat exchanger are different. Of course, this embodiment can alsoadopt the design of disposing the convex ridge 2 a on the firstcorrugation 1 so that the volumes of the inter-plate channels aredifferent, which will not be described in detail here.

In this embodiment, only part of the corrugation of one of the adjacentheat exchange plates is changed, so that the corrugation height of thispart is different from the overall corrugation height of the heatexchange plate. That is, one side of the inter-plate channel is asymmetrical heat exchange plate, and the other side is an asymmetricalheat exchange plate, so that the adjacent first channel 6 and the secondchannel 7 have different volumes. With this arrangement, the pressureloss is small, the heat exchange efficiency of the plate heat exchangeris improved, but the volume difference between the adjacent firstchannel 6 and the second channel 7 will not be too large to affect theheat exchange performance. During the heat exchange process of the plateheat exchanger, the medium flows through the first channel 6 and thesecond channel 7. The flow pressure drop of the medium in theinter-plate channel with a smaller volume increases, which increases theturbulence of the medium fluid, improves the heat exchange effect of themedium in the heat exchanger, and improves the heat exchangeperformance. On the other side, due to the increase in the volume of theinter-plate channel, the flow pressure drop of the medium issignificantly reduced, and the turbulence is slowed down, which can beused to circulate high-pressure medium to reduce the pressure drop andimprove the heat exchange performance. In this embodiment, by changingpart of the corrugations, compared with forming several grooves on thecorrugations to make the volumes of the inter-plate channels different,it is more convenient to process.

Due to the arrangement of the convex ridge 2 a, the network-shapedmulti-point contact points between the heat exchange plates are reduced.In order to ensure the connection strength between the heat exchangeplates, and the welding strength of the tops of the wave crests and thewave troughs which are in contact with the tops of the wave crests, atleast one of the ratios of W₁/h and W₂/h is with a range of 0.3 to 1,for example, the ratio is 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65,0.7, 0.75, 0.8, 0.85, 0.9, 1, etc. The present disclosure not onlyimproves the heat exchange performance and heat exchange efficiency ofthe heat exchanger, but also ensures high welding strength and improvesthe working stability of the plate heat exchanger. In this embodiment,the optional values of W₁/h and W₂/h are both within the range of 0.3 to1.

Referring to FIG. 7 again, in this embodiment, the wavelength λ of theconvex ridge 2 a (that is, a distance between two wave troughs adjacentto the convex ridge 2 a) is substantially the same as the wavelength λof the first wave crest 1 r, the first wave trough 1 g, the second wavecrest 2 r and the second wave trough 2 g. The tops of the convex ridges2 a of the same second heat exchange plate 20 are substantially locatedin a fifth plane P5. The fifth plane P5 is located between the thirdplane P3 and the fourth plane P4 of the same second heat exchange plate20. The fifth plane P5 is substantially parallel to the third plane P3.A height d of the convex ridge 2 a is a distance from the fifth plane P5to the fourth plane P4 of the same second heat exchange plate 20, whered=(0.4˜0.75)*h. The height d of the convex ridge 2 a is limited in orderto prevent the heat exchange performance of the heat exchanger frombeing too low or too high.

Since the convex ridge 2 a is provided, the first side wall portion 3 band the second side wall portion 3 c of the second wave trough 2 gadjacent to the convex ridge 2 a are asymmetrical with respect to thestraight portion 3 a, as shown in FIG. 11 .

In this embodiment, at least one convex ridge 2 a is provided on thesecond corrugation 2 at every interval of at least one second wave crest2 r. The convex ridge 2 a is distributed along the direction of theshortest line connecting the tops of the adjacent second wave crests 2 rof the second heat exchange plate 20. That is, at least one convex ridge2 a is provided between adjacent second wave crests 2 r, and at leastone second wave crest 2 r is provided between adjacent convex ridges 2a. For the convenience of understanding, the following examples willillustrate different implementation manners:

First implementation manner: as shown in FIG. 8 , the second corrugation2 is provided with a convex ridge 2 a at every interval of the secondwave crest 2 r. That is, the second wave crest 2 r-the convex ridge 2 aare arranged in sequence, and the second wave trough 2 g is locatedbetween adjacent second wave crest 2 r and convex ridge 2 a.

Second implementation manner: as shown in FIG. 9 , the secondcorrugation 2 is provided with two convex ridges 2 a at every intervalof the second wave crest 2 r. That is, the second wave crest 2 r-theconvex ridge 2 a-the convex ridge 2 a are arranged in sequence. Thesecond wave troughs 2 g are provided between adjacent second wave crest2 r and convex ridge 2 a, and between adjacent convex ridges 2 a.

Third implementation manner: as shown in FIG. 10 , the secondcorrugation 2 is provided with a convex ridge 2 a at every interval oftwo second wave crests 2 r. That is, the second wave crest 2 r-thesecond wave crest 2 r-the convex ridge 2 a are arranged in sequence. Thesecond wave troughs 2 g are provided between adjacent second wave crest2 r and the convex ridge 2 a, and between adjacent second wave crests 2r.

The arrangements of the convex ridge 2 a on the second corrugation 2 aremerely examples, but not limited thereto. The present disclosure mayalso adopt that the second wave crest 2 r-the second wave crest 2 r-theconvex ridge 2 a-the convex ridge 2 a are arranged in sequence. Otherarrangements may also be adopted, and appropriate arrangements can beselected according to heat exchange requirements.

Of course, in this embodiment, the tops of the convex ridges 2 a of thesame second heat exchange plate 20 may not be in the same plane, thatis, the convex ridges 2 a have different heights d.

Third Embodiment

In this embodiment, the parts that are the same as those in the firstand the second embodiments are given the same reference numerals, andthe same text descriptions are omitted.

Compared with the first embodiment and the second embodiment, the plateheat exchanger provided in this embodiment has the following designs:

Referring to FIG. 12 to FIG. 14 , the first heat exchange plate 10 andthe second heat exchange plate 20 are rectangular, including two shortsides 3 d and two long sides 3 e. The first corrugation 1 includes afirst flow guiding section 4. The second corrugation 2 includes a secondflow guiding section 5. An opening angle β1 of the first flow guidingsection 4 is the same as an opening angle β2 of the second flow guidingsection 5. A direction of the opening angle β1 of the first flow guidingsection 4 is opposite to a direction of the opening angle β2 of thesecond flow guiding section 5. Through the reverse combination of thefirst corrugation 1 of the first heat exchange plate 10 and the secondcorrugation 2 of the second heat exchange plate 20, a network-shapedmulti-point contact is formed. Moreover, under the action of thecorrugations, the fluid medium forms turbulent flow in the inter-platechannels at a lower Reynolds number, which improves the heat exchangeeffect and helps to reduce the fouling of the heat exchange plates.

In order to improve the heat exchange performance, in this embodiment,the first flow guiding section 4 and the second flow guiding section 5may be distributed in a V-shape or a W-shape, etc., which will bedescribed in detail below through different implementation manners.

First implementation manner: referring to FIG. 12 and FIG. 13 again, thefirst flow guiding section 4 includes a first flow guiding subsection 4a and a second flow guiding subsection 4 b. The connection between thefirst flow guiding subsection 4 a and the second flow guiding subsection4 b forms a V shape, and forms an opening angle β1. The first flowguiding section 4 a and the second flow guiding section 4 b aresymmetrical with respect to a center line 1. The center line l isperpendicular to the two short sides 3 d. Correspondingly, the secondcorrugation 2 includes a second flow guiding section 5. The second flowguiding section 5 includes a third flow guiding subsection 5 a and afourth flow guiding subsection 5 b. The third flow guiding subsection 5a and the fourth flow guiding subsection 5 b are connected, and form anopening angle β2.

Second implementation manner: referring to FIG. 15 and FIG. 16 , thefirst flow guiding section 4 includes two first flow guiding subsections4 a and one second flow guiding subsection 4 b. The first flow guidesubsections 4 a and the second flow guide subsection 4 b are alternatelydistributed along a direction of the short side of the heat exchangeplate. Adjacent first flow guiding subsection 4 a and second flowguiding subsection 4 b are connected, and form an opening angle β1. Thefirst flow guiding section 4 a and the second flow guiding section 4 bare symmetrical with respect to a center line l′. The center line l′ isperpendicular to the two short sides. Correspondingly, the secondcorrugation 2 includes a second flow guiding section 5. The second flowguiding section 5 includes two third flow guiding subsections 5 a and afourth flow guiding subsection 5 b. The third flow guide subsections 5 aand the fourth flow guide subsection 5 b are alternately distributedalong the direction of the short side of the heat exchange plate.Adjacent third flow guiding subsection 5 a and fourth flow guidingsubsection 5 b are connected, and form an opening angle β2.

Third implementation manner: referring to FIG. 17 and FIG. 18 , on thebasis of the second implementation manner, this embodiment adds a secondflow guiding subsection 4 b to the first flow guiding section 4, andadds a fourth flow guiding subsection 5 b to the second flow guidingsection 5, so that the first flow guiding section 4 is W-shaped and thesecond flow guiding section 5 is a reverse W shape.

The above is just examples of the distribution of some flow guidingsections, but it is not limited to this, and it can also be distributedin 3-fold V-shape or even more heavy-V-shape. Moreover, the openingangles on the same heat exchange plate can be the same or different.

Further, the opening angle of the corrugation is selected to be large,for example 90°≤β1(β2)≤135°, to increase the heat exchange coefficientso as to obtain more heat exchange.

Part of the technical implementations of the first to third embodimentsabove may be combined or replaced.

Referring to FIG. 12 and FIG. 13 again in conjunction with FIGS. 19-20 ,in the above embodiment, the first heat exchange plate 10 is providedwith four first ports 8 a. Two first ports 8 a are located in a sameplane as the bottom of the first wave trough 1 g of the first heatexchange plate 10. Another two first ports 8 a are in a same plane asthe top of the first wave crest 1 r of the first heat exchange plate 10.The four first ports 8 a are located at four corners of the first heatexchange plate 10, respectively. The second heat exchange plate 20 isprovided with four second ports 8 b. Two second ports 8 b are located ina same plane as the top of the second wave crest 2 r of the same secondheat exchange plate 20. Another two second ports 8 b are located in asame plane as the bottom of the second wave trough 2 g of the samesecond heat exchange plate 20. The four second ports 8 b are located atfour corners of the second heat exchange plate 20, respectively.Positions of the second ports 8 b of the second heat exchange plate 20correspond to positions of the first ports 8 a of the adjacent firstheat exchange plate 10. In the adjacent first heat exchange plate 10 andsecond heat exchange plate 20, two pairs of corresponding first ports 8a and second ports 8 b are fitted together, and another two pairs arespaced apart from each other with gaps to communicate with correspondinginter-panel channels. Further, the two pairs of first ports 8 a andsecond ports 8 b that fit together are distributed diagonally. In otherwords, the first port 8 a and the second port 8 b with gaps are alsodistributed diagonally. When the plate heat exchanger is configured forthe heat exchange process, the medium flows into the correspondinginter-plate channel from a position between a pair of first port 8 a andthe second port 8 b with the gap, and the medium flows out from aposition between the first port 8 a and the second port 8 b with the gapdiagonally across. Of course, in the above embodiment, the first port 8a and the second port 8 b with gaps can also be distributed on the sameside and close to the long sides.

Further, in order to improve the structural strength of the corners ofthe first port 8 a and the second port 8 b with gaps, in the paired andspaced first port 8 a and the second port 8 b with gaps, the first heatexchange plate 10 is provided with a first support portion 8 c at thecorner where the first port 8 a is located, and the second heat exchangeplate 20 is provided with a second support portion 8 d at the cornerwhere the second port 8 b is located. Both the first support portion 8 cand the second support portion 8 d protrude toward the gap and abutagainst each other. By arranging the first support portion 8 c and thesecond support portion 8 d, a periphery of the first port 8 a and thesecond port 8 b with gaps form an effective support, thereby improvingthe structural strength. Wherein, the first support portion 8 c and thesecond support portion 8 d are protrusions or grooves formed bypressing.

Further, referring to FIG. 21 , in the above embodiment, an outerperiphery of the first heat exchange plate 10 has a first skirt 9 a, andan outer periphery of the second heat exchange plate 20 has a secondskirt 9 b. The first skirt 9 a of the first heat exchange plate 10 is atleast partially overlapped with the second skirt 9 b of the adjacentsecond heat exchange plate 20 and surrounds a corresponding inter-platechannel. In addition, referring to FIG. 1 and FIG. 2 again, in the aboveembodiment, the plate heat exchanger further includes connecting pipes 9c and blocking elements 9 d. The first port 8 a or the second port 8 bon one side of the plate heat exchanger along the stacking direction isconnected to one connecting pipe 9 c, and the first port 8 a or thesecond port 8 b on the other side is provided with one blocking element9 d. That is, each port of the first heat exchange plate of the plateheat exchanger is respectively connected with one connecting pipe 9 c,and each port of the last heat exchange plate is provided with oneblocking element 9 d for blocking. The blocking element 9 d may be agasket. Of course, the last heat exchange plate can also not be providedwith a port.

The above embodiments are only used to illustrate the present disclosureand not to limit the technical solutions described in the presentdisclosure. The understanding of this specification should be based onthose skilled in the art. Descriptions of directions, although they havebeen described in detail in the above-mentioned embodiments of thepresent disclosure, those skilled in the art should understand thatmodifications or equivalent substitutions can still be made to theapplication, and all technical solutions and improvements that do notdepart from the spirit and scope of the application should be covered bythe claims of the application.

What is claimed is:
 1. A plate heat exchanger, comprising: a pluralityof first heat exchange plates, the first heat exchange plate comprisinga first corrugation, the first corrugation comprising a first wave crestand a first wave trough; and a plurality of second heat exchange plates,the second heat exchange plate comprising a second corrugation, thesecond corrugation comprising a second wave crest and a second wavetrough; wherein the first heat exchange plate and the second heatexchange plate are stacked alternately along a stacking direction whichis the same as a thickness direction of the plate heat exchanger; atleast part of the second wave crest of the second heat exchange plate isin contact with a corresponding first wave trough of an adjacent firstheat exchange plate which is located adjacent to the second heatexchange plate; at least part of the second wave trough of the secondheat exchange plate is in contact with a corresponding first wave crestof another adjacent first heat exchange plate which is located adjacentto the second heat exchange plate; along the thickness direction of theplate heat exchanger, a maximum distance between the first wave crest ofthe first heat exchange plate and the first wave trough of the firstheat exchange plate is h; and in a direction of a shortest lineconnecting tops of adjacent first wave crests, in adjacent first heatexchange plate and second heat exchange plate, a minimum connectingwidth of the first wave trough and the second wave crest is W₁, and aminimum connecting width of the first wave crest and the second wavetrough is W₂; wherein at least one of a ratio of W₁/h and a ratio ofW₂/h is within a range of 0.25 to 2.5.
 2. The plate heat exchangeraccording to claim 1, wherein along the thickness direction of the plateheat exchanger, a maximum distance between the second wave crest of thesecond heat exchange plate and the second wave trough of the second heatexchange plate is h; in the direction of the shortest line connectingthe tops of the adjacent first wave crests, an outer width of a bottomof the first wave trough connected to the second wave crest is greaterthan or equal to W₁, an outer width of a top of the second wave crestconnected to the first wave trough is greater than or equal to W₁, anouter width of a top of the first wave crest connected to the secondwave trough is greater than or equal to W₂, and an outer width of abottom of the second wave trough connected to the first wave crest isgreater than or equal to W₂; wherein at least one of a ratio of W₁/h anda ratio of W₂/h is within a range of 0.3 to
 1. 3. The plate heatexchanger according to claim 2, wherein in the direction of the shortestline connecting the tops of the adjacent first wave crests, the outerwidth of the bottom of the first wave trough connected to the secondwave crest is W₁, the outer width of the top of the second wave crestconnected to the first wave trough is W₁, the outer width of the top ofthe first wave crest connected to the second wave trough is W₂, and theouter width of the bottom of the second wave trough connected to thefirst wave crest is W₂; and wherein W₁ is the same as W₂.
 4. The plateheat exchanger according to claim 1, wherein at least part of a topsurface of the first wave crest of the first heat exchange plate islocated in a first plane P1, at least part of a bottom surface of thefirst wave trough is located in a second plane P2, the first plane P1 isparallel to the second plane P2, and a distance from the first plane P1to the second plane P2 is the same as h; at least part of a top surfaceof the second wave crest of the second heat exchange plate is located ina third plane P3, at least part of a bottom surface of the second wavetrough is located in a fourth plane P4, the third plane P3 is parallelto the fourth plane P4, and a distance from the third plane P3 to thefourth plane P4 is the same as h; the third plane P3 of the second heatexchange plate coincides with the second plane P2 of the adjacent firstheat exchange plate, and the fourth plane P4 of the second heat exchangeplate coincides with the first plane P1 of the another adjacent firstheat exchange plate; the thickness direction of the plate heat exchangeris perpendicular to the first plane P1.
 5. The plate heat exchangeraccording to claim 1, wherein the top of the first wave crest, a top ofthe second wave crest, a bottom of the first wave trough and a bottom ofthe second wave trough are straight portions; a contact surface of thestraight portion is perpendicular to the thickness direction of theplate heat exchanger; the first wave crest, the second wave crest, thefirst wave trough and the second wave trough further comprise a firstside wall portion and a second side wall portion; in the direction ofthe shortest line connecting the tops of the adjacent first wave crests,one side of the straight portion is connected to the first side wallportion, and another side of the straight portion is connected to thesecond side wall portion; an included angle a is formed between thefirst side wall portion and the second side wall portion, where120°≤α≤135°.
 6. The plate heat exchanger according to claim 1, whereinthe second corrugation further comprises at least one convex ridge whichis distributed along a direction of a shortest line connecting tops ofadjacent second wave crests of the second heat exchange plate; along thethickness direction of the plate heat exchanger, a top of the convexridge is located between the top of the second wave crest and a bottomof the second wave trough; along the thickness direction of the plateheat exchanger, volumes of inter-plate channels on two sides of theconvex ridge of the plate heat exchanger are different; the top of theconvex ridge of the second heat exchange plate is located in a fifthplane P5, the fifth plane P5 is located between a third plane P3 and afourth plane P4 of the same second heat exchange plate; the fifth planeP5 is parallel to the third plane P3, a height d of the convex ridge isa distance from the fifth plane P5 to the fourth plane P4, whered=(0.4˜0.75)*h; and wherein h is 1˜2 mm.
 7. The plate heat exchangeraccording to claim 6, wherein at least one convex ridge is arrangedbetween adjacent second wave crests, at least one second wave crest isarranged between adjacent convex ridges; the inter-plate channels of theplate heat exchanger comprise at least one first channel and at leastone second channel; the first channel is located between the second heatexchange plate and the adjacent first heat exchange plate; the secondchannel is located between the second heat exchange plate and theanother adjacent first heat exchange plate; the first channel and thesecond channels are located on two sides of a same convex ridge,respectively, along the thickness direction of the plate heat exchanger;volumes of the first channel and the second channel are different; thefirst channels communicate with each other, the second channelscommunicate with each other, and the first channel and the secondchannel do not communicate with each other.
 8. The plate heat exchangeraccording to claim 1, wherein both the first heat exchange plate and thesecond heat exchange plate comprise two short sides and two long sides;the first corrugation comprises a first flow guiding section; the firstflow guiding section comprises at least one first flow guidingsubsection and at least one second flow guiding subsection; adjacentfirst guiding subsection and second guiding subsection are connected toform an opening angle β1, where 90°≤β1≤135°; the first guiding sectionand the second guiding section are symmetrical about a center line l,and the center line l is perpendicular to the two short sides; thesecond corrugation comprises a second flow guiding section; the secondflow guiding section comprises at least one third flow guidingsubsection and at least one fourth flow guiding subsection; adjacentthird flow guiding subsection and fourth flow guiding subsection areconnected to form an opening angle β2, where 90°≤β2≤135°; the openingangle β1 of the first flow guiding section is the same as the openingangle β2 of the second flow guiding section; a direction of the openingangle β1 of the first flow guiding section is opposite to a direction ofthe opening angle β2 of the second flow guiding section.
 9. The plateheat exchanger according to claim 1, wherein the first heat exchangeplate is opened with four first ports, in which two first ports are in asame plane as a bottom of the first wave trough of the same first heatexchange plate, and another two first ports are in a same plane as thetop of the first wave crest of the same first heat exchange plate; thefour first ports are located at four corners of the first heat exchangeplate, respectively; the second heat exchange plate is opened with foursecond ports, in which two second ports are in a same plane as a top ofthe second wave crest of the same second heat exchange plate, andanother two second ports are in a same plane as a bottom of the secondwave trough of the same second heat exchange plate; the four secondports are located at four corners of the second heat exchange plate,respectively; positions of the second ports of the second heat exchangeplate correspond to positions of the first ports of the adjacent firstheat exchange plate; in adjacent first heat exchange plate and secondheat exchange plate, two pairs of corresponding first ports and secondports are fitted together, and another two pairs are arranged atintervals with gaps; the two pairs of fitted first ports and secondports are diagonally distributed.
 10. The plate heat exchanger accordingto claim 9, wherein in the first port and the second port arranged atintervals with gaps, the first heat exchange plate is provided with afirst support portion at a corner where the first ports are located, andthe second heat exchange plate is provided with a second support portionat a corner where the second ports are located; both the first supportportion and the second support portion protrude toward the gap and abutagainst each other; an outer periphery of the first heat exchange plateis provided with a first skirt, an outer periphery of the second heatexchange plate is provided with a second skirt, the first skirt of thefirst heat exchange plate is at least partially overlapped with thesecond skirt of an adjacent second heat exchange plate so as to surrounda corresponding inter-plate channel; the plate heat exchanger furthercomprises connecting pipes and blocking elements, the first port or thesecond port on one side of the plate heat exchanger along the thicknessdirection of the plate heat exchanger is respectively connected with oneconnecting pipe; the first port or the second port on another side isprovided with one blocking element.
 11. A plate heat exchanger,comprising: a plurality of first heat exchange plates, each first heatexchange plate comprising a first corrugation, the first corrugationcomprising a plurality of first wave crests and a plurality of firstwave troughs; and a plurality of second heat exchange plates, eachsecond heat exchange plate comprising a second corrugation, the secondcorrugation comprising a plurality of second wave crests and a pluralityof second wave troughs; wherein the first heat exchange plate and thesecond heat exchange plate are stacked alternately along a firstdirection of the plate heat exchanger; at least part of the second wavecrests of the second heat exchange plate are fixed to correspondingfirst wave troughs of an upper adjacent first heat exchange plate; atleast part of the second wave troughs of the second heat exchange plateare fixed to corresponding first wave crests of a lower adjacent firstheat exchange plate; along the first direction of the plate heatexchanger, a maximum distance between the first wave crest of the firstheat exchange plate and the first wave trough of the first heat exchangeplate is h; a top of the first wave crest and a bottom of the first wavetrough are flat, and a top of the second wave crest and a bottom of thesecond wave trough are flat; in a second direction perpendicular to thefirst direction, in adjacent first heat exchange plate and second heatexchange plate, a minimum connecting width of the first wave trough andthe second wave crest is W₁, and a minimum connecting width of the firstwave crest and the second wave trough is W₂; wherein at least one of aratio of W₁/h and a ratio of W₂/h is within a range of 0.25 to 2.5. 12.The plate heat exchanger according to claim 11, wherein along the firstdirection of the plate heat exchanger, a maximum distance between thesecond wave crest of the second heat exchange plate and the second wavetrough of the second heat exchange plate is h; in the direction of ashortest line connecting the tops of the adjacent first wave crests, anouter width of a bottom of the first wave trough connected to the secondwave crest is greater than or equal to W₁, an outer width of the secondwave crest connected to the first wave trough is greater than or equalto W₁, an outer width of the first wave crest connected to the secondwave trough is greater than or equal to W₂, and an outer width of abottom of the second wave trough connected to the first wave crest isgreater than or equal to W₂; wherein at least one of a ratio of W₁/h anda ratio of W₂/h is within a range of 0.3 to
 1. 13. The plate heatexchanger according to claim 12, wherein in the direction of theshortest line connecting the tops of the adjacent first wave crests, theouter width of the bottom of the first wave trough connected to thesecond wave crest is W₁, the outer width of the second wave crestconnected to the first wave trough is W₁, the outer width of the firstwave crest connected to the second wave trough is W₂, and the outerwidth of a bottom of the second wave trough connected to the first wavecrest is W₂; and wherein W₁ is the same as W₂.
 14. The plate heatexchanger according to claim 11, wherein at least part of a top surfaceof the first wave crest of the first heat exchange plate is located in afirst plane P1, at least part of a bottom surface of the first wavetrough is located in a second plane P2, the first plane P1 is parallelto the second plane P2, and a distance from the first plane P1 to thesecond plane P2 is the same as h; at least part of a top surface of thesecond wave crest of the second heat exchange plate is located in athird plane P3, at least part of a bottom surface of the second wavetrough is located in a fourth plane P4, the third plane P3 is parallelto the fourth plane P4, and a distance from the third plane P3 to thefourth plane P4 is the same as h; the third plane P3 of the second heatexchange plate coincides with the second plane P2 of the adjacent firstheat exchange plate, and the fourth plane P4 of the second heat exchangeplate coincides with the first plane P1 of the another adjacent firstheat exchange plate; the first direction of the plate heat exchanger isperpendicular to the first plane P1.
 15. The plate heat exchangeraccording to claim 11, wherein the second corrugation further comprisesat least one convex ridge which is distributed along a direction of ashortest line connecting tops of adjacent second wave crests of thesecond heat exchange plate; along the first direction of the plate heatexchanger, a top of the convex ridge is located between the top of thesecond wave crest and a bottom of the second wave trough; along thefirst direction of the plate heat exchanger, volumes of inter-platechannels on two sides of the convex ridge of the plate heat exchangerare different; the top of the convex ridge of the second heat exchangeplate is located in a fifth plane P5, the fifth plane P5 is locatedbetween a third plane P3 and a fourth plane P4 of the same second heatexchange plate; the fifth plane P5 is parallel to the third plane P3, aheight d of the convex ridge is a distance from the fifth plane P5 tothe fourth plane P4, where d=(0.4˜0.75)*h; and wherein h is 1˜2 mm. 16.The plate heat exchanger according to claim 15, wherein at least oneconvex ridge is arranged between adjacent second wave crests, at leastone second wave crest is arranged between adjacent convex ridges; theinter-plate channels of the plate heat exchanger comprise at least onefirst channel and at least one second channel; the first channel islocated between the second heat exchange plate and the adjacent firstheat exchange plate; the second channel is located between the secondheat exchange plate and the another adjacent first heat exchange plate;the first channel and the second channels are located on two sides of asame convex ridge, respectively, along the first direction of the plateheat exchanger; volumes of the first channel and the second channel aredifferent; the first channels communicate with each other, the secondchannels communicate with each other, and the first channel and thesecond channel do not communicate with each other.
 17. The plate heatexchanger according to claim 11, wherein both the first heat exchangeplate and the second heat exchange plate comprise two short sides andtwo long sides; the first corrugation comprises a first flow guidingsection; the first flow guiding section comprises at least one firstflow guiding subsection and at least one second flow guiding subsection;adjacent first guiding subsection and second guiding subsection areconnected to form an opening angle β1, where 90°≤β1≤135°; the firstguiding section and the second guiding section are symmetrical about acenter line l, and the center line l is perpendicular to the two shortsides; the second corrugation comprises a second flow guiding section;the second flow guiding section comprises at least one third flowguiding subsection and at least one fourth flow guiding subsection;adjacent third flow guiding subsection and fourth flow guidingsubsection are connected to form an opening angle β2, where 90°≤β2≤135°;the opening angle β1 of the first flow guiding section is the same asthe opening angle β2 of the second flow guiding section; a direction ofthe opening angle β1 of the first flow guiding section is opposite to adirection of the opening angle β2 of the second flow guiding section.18. The plate heat exchanger according to claim 11, wherein the firstheat exchange plate is opened with four first ports, in which two firstports are in a same plane as a bottom of the first wave trough of thesame first heat exchange plate, and another two first ports are in asame plane as the top of the first wave crest of the same first heatexchange plate; the four first ports are located at four corners of thefirst heat exchange plate, respectively; the second heat exchange plateis opened with four second ports, in which two second ports are in asame plane as a top of the second wave crest of the same second heatexchange plate, and another two second ports are in a same plane as abottom of the second wave trough of the same second heat exchange plate;the four second ports are located at four corners of the second heatexchange plate, respectively; positions of the second ports of thesecond heat exchange plate correspond to positions of the first ports ofthe adjacent first heat exchange plate; in adjacent first heat exchangeplate and second heat exchange plate, two pairs of corresponding firstports and second ports are fitted together, and another two pairs arearranged at intervals with gaps; the two pairs of fitted first ports andsecond ports are diagonally distributed.
 19. The plate heat exchangeraccording to claim 18, wherein in the first ports and the second portsarranged at intervals with gaps, the first heat exchange plate isprovided with a first support portion at a corner where the first portsare located, and the second heat exchange plate is provided with asecond support portion at a corner where the second ports are located;both the first support portion and the second support portion protrudetoward the gap and abut against each other; an outer periphery of thefirst heat exchange plate is provided with a first skirt, an outerperiphery of the second heat exchange plate is provided with a secondskirt, the first skirt of the first heat exchange plate is at leastpartially overlapped with the second skirt of an adjacent second heatexchange plate so as to surround a corresponding inter-plate channel;the plate heat exchanger further comprises connecting pipes and blockingelements, the first port or the second port on one side of the plateheat exchanger along the first direction of the plate heat exchanger isrespectively connected with one connecting pipe; the first port or thesecond port on another side is provided with one blocking element.
 20. Aplate heat exchanger, comprising: a plurality of first plates, the firstplate having a first corrugation comprising a first wave crest and afirst wave trough; and a plurality of second heat exchange plates, thesecond heat exchange plate having a second corrugation comprising asecond wave crest and a second wave trough, the first heat exchangeplates and the second heat exchange plates being stacked alternatelyalong a height direction of the plate heat exchanger; wherein at leastpart of the second wave crest of the second heat exchange plate is incontact with a corresponding first wave trough of an adjacent first heatexchange plate located adjacent to the second heat exchange plate, atleast part of the second wave trough of the second heat exchange plateis in contact with a corresponding first wave crest of another adjacentfirst heat exchange plate located adjacent to the second heat exchangeplate; the plate heat exchanger defines a plurality of first channelsand a plurality second channels disposed alternately along the heightdirection, the first channel is located between the second heat exchangeplate and the adjacent first heat exchange plate, the second channel islocated between the second heat exchange plate and the another adjacentfirst heat exchange plate, and volumes of the first channel and thesecond channel are different; and a minimum connecting width of thefirst wave trough and the second wave crest is W₁, a minimum connectingwidth of the first wave crest and the second wave trough is W₂, andvalues of W₁ and W₂ are different.